The structure and composition of the yeast plasma membrane will be further studied. The purification of solubilized chitin synthetase will be pursued, with a view to determine the minimal size of an enzymatic complex that can manufacture a fibril in vitro. Further efforts will be made towards obtaining mutants defective in chitin synthesis and towards development of a method to detect specifically chitin at the electron microscope level of resolution. An enzymatic system from yeast that catalyzes the synthesis of a Beta-glucan will be further studied, in an attempt to understand its requirements and the mechanisms of the reaction.